Looking at buying a 9000 aero

Hello,

Looking at buying a 9000 aero preferably between 1995-1997. I currently have a 1988 900 aero and will be selling it shortly. Just wanted to know if all the 9000 aero models from 1994-1997 (manuals) had forged cranks and pistons or was it only the later models? Also when did the turbo change?

Would also appreciate if anyone had any advice on what to look out for when buying a 9000 aero? I've read the cooling system can be a problem as well as the TCS. Any other problems or issues?

Thanks in advance!